New evidence has recently been unearthed about Australia’s kangaroos. Their ancient ancestor can now be traced back 24 million years to Palaeopotorous—the starting point of all known kangaroo species. Fossils of a few small teeth were discovered in the hot Australian desert, hidden away in a museum for thirty years, and nearly forgotten until now.

It’s a timely and interesting discovery, given the acclaimed new feature-length documentary, "Kangaroo," which premiered in the United States this year.

The U.S. is one of the world's leading markets for kangaroo meat and skins. And the Australian government, together with the commercial kangaroo industry, is actively lobbying the U.S. as a key growth market and trying to increase exports to the U.K. and the European Union—and get a foothold in new markets like China.

The lucrative kangaroo industry—the largest land-based slaughter of wildlife on Earth—is predicated on the assumption that kangaroos are pests. However, the logic of a 24-million-year-old animal, uniquely evolved to the Australian ecosystem, labeled a 'pest' is questionable.

Millions of cattle and sheep now roam the Australian landscape, introduced in the late 1700s and, unlike kangaroos, they compact the delicate topsoil with their hard hooves, causing erosion. They also contribute a massive 11 percent of Australia's greenhouse gas emissions. Rather than being labeled a pest, cattle and sheep are celebrated for their economic value.

The other justification for the kangaroo industry is overpopulation. However, this is also debatable, given that survey methodology is arguably flawed and, according to leading kangaroo scientists, the populations of different kangaroo species (four species are killed by the industry– the Red kangaroo, Eastern and Western Grey kangaroo and the Common Wallaroo) go up and down in natural patterns, influenced by weather, environmental conditions, birth rate and other factors.

Accusations of kangaroos being overpopulated pests aside, the major concern for kangaroos in Australia is the inherent cruelty of the industry.

One scene in "Kangaroo" is hard to watch. A small baby kangaroo, or "joey," too young and fragile to survive alone, attempts to hop away from his dead mother but is unable. The joey is clearly doomed to a slow death. The camera observes passively, as in all documentaries, taking no action. However, as viewers, we have faith that this individual animal, once the cameras stop, will be rescued by the film crew.

This joey might have gotten lucky but the other hundreds of thousands are not. Every night, across Australia's remote outback, joeys and young-at-foot (young, still dependent kangaroos), who depend on their mothers for survival, are killed or left to die after slowly suffering. They are considered "by-products" of the industry.

According to Australia's National Code of Practice, female kangaroos with joeys (both pouch-young and young-at-foot) are meant to be avoided in the kill but this is voluntary, not compulsory. If they are shot, the dependent young are supposed to be "humanely" disposed of—by beating them on the head on the back of a truck. But how high is non-compliance?

Nobody checks how joeys are killed or monitors the speed of their death ensuring it is "instantaneous" as the Code recommends. In reality, the shooter is alone with the animal, sometimes a thousand kilometers from any human population, with no obligation to report the joey or young-at-foot's life or death. There are no witnesses, records or oversight. We rely only on the shooter's conscience to ensure the baby is killed quickly or killed at all. Joeys not immediately killed suffer a worse fate—left without maternal care they die of starvation, dehydration or predation.

There is no way that the welfare of joeys can ever be protected in Australia's commercial kangaroo industry. Even if the industry mandates that no females are killed, which has its own complex ecological consequences, there is no ability to police it. The expenses to the industry and subsequent cost of meat and skins would prevent proper inspection. For example, an inspector accompanying every shooter on every hunt is impossibly costly. And conducting a spot-inspection when a shooter is driving through the bush at 2 am, a thousand miles from any town center, is practically impossible.

Why should we care? Of course, a kangaroo baby is not the same as a human baby. However, both are sentient beings, suffer pain and distress, have complex emotional responses and instincts to call their mother when in trouble. Both need warmth, food and care.

Kangaroos are highly social animals who live in large groups called mobs, and mothers and joeys have close relationships and unique calls to communicate to each other. Studies show that female Eastern Grey Kangaroos recognize the individual voices of their young, and mothers and daughters maintain long-term bonds.

Thanks to the film "Kangaroo," a light is finally being shined on the cruelty that is inflicted on of one of the world’s most beloved and celebrated animal. And even if Australians are still prepared to bury their heads, Americans can speak out. We must all raise our voices for kangaroos and help ensure their welfare and survival.

Want to help make a difference? Don’t buy kangaroo meat or leather (labeled "K-leather"), write to your supermarket and ask them not to stock kangaroo meat and host your own screening of "Kangaroo in your town or city." Learn more about kangaroos here.

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Ondine Sherman is co-founder and managing director of Voiceless: The Animal Protection Institute, based in New South Wales, Australia. She is the author, most recently, of Sky (2017, The Author People), the first in a series of YA books about a young vegan Australian.